Photonics group

The Photonics Group at Surrey is a world leader in research on semiconductor optoelectronics.

The electronic and optical properties of 'designer semiconductors' are engineered on the length scale of an electron or photon wavelength. We investigate 'electron boxes' (from quantum wells to quantum dots), 'optical boxes' (microcavities and vertical-cavity lasers), and new materials such as dilute nitride-containing semiconductors. Such semiconductor nanostructures are an example of the direct application of quantum mechanics to improve real-world devices such as lasers in CD players or optical communications, and are essential hardware for the ultra-high speed optical communications underpinning the information technology revolution.

The group at Surrey is active in many aspects of this field. For example:

• Major advances have been made by the group in measuring the energy bands of key 'photonic' semiconductors (which unlike silicon interact strongly with infrared light), and then in designing, characterising and optimising optoelectronic devices. A particular success of the Surrey group was the prediction of the superior properties of semiconductor lasers employing strained layers, which are now ubiquitous in the industry.
• A speciality is the use of hydrostatic pressure as a diagnostic tool to perturb the semiconductor properties, which are measured with a wide range of experimental techniques.
• Devices that operate in the mid-infrared are studied with the aid of a Free Electron Laser located in Holland; such devices have important applications in environmental sensors.
• Advanced experimental techniques include the use of cryogenic temperatures, high magnetic fields, and high pressures to perturb the properties of the semiconductor, and novel optical characterisation methods.
• Another major activity uses a new ultrafast laser facility at Surrey to study dynamics on the femtosecond (10^-15 s) time scale, a regime which is critical for future ultra-broadband terabit-per-second communications.
• All of the group's activities are underpinned by a strong theoretical effort, ranging from the study of fundamental electron-photon interactions to calculating the optical and electronic properties of semiconductor alloys, strained-layers and nanostructures.

The group is comprised of eight academic staff, conducting tightly-coupled experimental and theoretical studies, with strong connections to leading companies in industry. Further details on the group are at: www.ati.surrey.ac.uk/photonics

The group is part of the Advanced Technology Institute (ATI), a £10 million investment with cutting-edge laboratory facilities for optoelectronics research. More information on the ATI can be found at the following website: www.ati.surrey.ac.uk